Research Methods

• an aim shows what we want to research eg to investigate whether drinking energy drinks makes people more talkative
• a hypothesis is a statement that is made at the start of a study and describes the relationship between variables
• a directional hypothesis is where there is a clear difference between the conditions in the hypothesis eg people who drink energy drinks are more talkative than people who don’t
• a non directional hypothesis just states that there is a difference between conditions eg people who drink energy drinks differ in talkativeness to people who don’t drink energy drinks
• experimental method involves the manipulation of an independant variable ( IV) to measure the effect on the dependant variable (DV). these can be laboratory, field, natural or quasi
• variables are anything that can change or vary within an investigation
• independant variables (IV) is an aspect of the situation that is manipulated by the researcher, or that changes naturally
• dependant variables (DV) are the variables that are measured by the researcher
• operationalisation is clearly defining variables in terms of how they can be measured
• there are 6 types of research issues :

  • extraneous variables
  • confounding variables
  • demand characteristics
  • investigator effects
  • randomisation
  • standardisation
• extraneous variables are any variables other than the IV that may affect the DV if it is not controlled
• confounding variables are a kind of EV but they vary systematically with the IV
• demand characteristics are any cure from the researcher or the situation that may be interpreted as exposing the purpose of an investigation which can lead to fake behaviour and less reliability
• investigator effects are any effects of the investigators behaviour on the research outcome eg the design of the study
• randomisation is the use of chance methods to control the effects of bias
• standardisation is using exactly the same procedures and instructions for all participants in a research study
• experimental design refers to the way in which participants are used in experiments
• independant groups design is when 2 seperate groups of participants experience two different conditions of the experiment.
• repeated measures is when all participants experience both conditions of the experiment
• matched pairs design is where participants are paired together on a variable or variables relevant to the experiment to control confounding variabled of participant variables
• negative - independent groups design has participants in different groups that are not the same in terms of participant variables. to deal with this, researchers use random allocation
• positive - independant groups design do not have order effects as a problem
• negative - independent groups designs are less economical than repeated measures
• negative - repeated measures means that the the order of the tasks are significant so to deal with this researchers use counterbalancing
• negative - repeated measures have order effects because repeating tasks can make boredom which deteriorates performance - confounding variable
• negative - repeated measures means that it’s more likely that participants will work out the aim of the study so demand characteristics are a feature
• positive - repeated measures design means that participant variables are controlled and fewer people are needed so higher validity
• positive - matched pairs mean that order effects and demand characteristics are less of a problem as participants take part in a single condition
• negative - in matched pairs, participants can never be matched exactly
• negative - in matched pairs, matching may be time consuming and expensive
• counterbalancing is an attempt to control the effects of order in a repeated measure design by making half of the participants experience the conditions in one order and the other half in the opposite order
• lab experiments take place in controlled environments where the researcher manipulates the IV and records the effect of the DV while keeping control of EV
• field experiments take place in a natural setting where the researcher manipulates the IV and records the effect on the DV
• natural experiments are where the change in the IV is not brought about by the researcher but happens naturally, and the researcher records the effect on the DV
• quasi experiments are a study where the IV has not been determined and the variables just exist eg being old or young
• strengths of lab experiments:

  • high control over confounding snd extraneous variables
  • high internal validity
  • replication is easier
• limitations of lab experiments:

  • lack generalisability
  • low external validity
  • demand characteristics are issue
  • low mundane realism
• strengths of field experiments:

  • higher mundane realism
  • high external validity
• limitations of field experiments:

  • loss of control of CVs and EVs
  • ethical issues eg invasion of privacy and consent
• strengths of natural experiments:

  • produce opportunities for research
  • high external validity